Whistle coming out of the Exhaust Pipe? Any Idea what it might be?

Been getting this weird high to moderate pitch noise coming out from the exhaust end when waiting on a light or at the start of complete stop...

So for the past week I've had this whistle that at first seemed to be the Serpentine Belt I was completely off even though it sounded like it would be that. I changed it I figured the noise will go away as soon as it was replaced. The belt look fine, no cracks or anything but figured why not start from there.

It didn't change the noise continued for 2 days until I was actually able to leave it on "Drive" and put the Emergency Brake, when I got off the truck I popped open the hood and strangely enough the sound was coming no where near the Serpentine Belt. The noise was coming from where the pipes from the exhaust turned down. It didn't seem to sound from anywhere but the end of the exhaust. There was no "start" of the noise I could only hear out the pipes. It a high pitch like "roof led bar" would make or a bad Serpentine Belt.

I took it took my exhaust guys and they found no leaks anywhere on the pipes...

Any idea what it might be? My exhaust has been like this for over a year and have not had a problem with any noises. Everything seems to run fine and no trouble codes.

 

Look for a small break in a weld.

 

Its that Toyota Turbo baby!!

 

Maybe Bub Rub knows...

https://youtu.be/JZD-ADArwXo

 

I had it checked it by two shops and they couldn't find it, the noise is not constant so they both argues it cant be the exhaust

 

hahaha you guys spend way to much time on youtube

 

Does it happen early in the morning? Sorry OP, I have nothing real to contribute to this thread.

https://www.youtube.com/watch?v=JZD-ADArwXo

 

did they run smoke through your intake out the exhaust looking for holes?

 

No its weird it actually does it once the truck is completely warmed up

 

yes

 

Always late to the party

 

I had a pea size hole that was missed on my exhaust that would whistle and add some ricer rasp at different rpm's is why I ask.

 

What muffler bearing oil are you using?

 

It's coming from the tips? because I had a similar problem, and it turned out to be the smallest hole in my exhaust header gasket. I replaced them and the whistle went away after that. Do you have aftermarket headers?

 

Yea I had this happen a while back when one of my mounts broke off but it happened everytime, this time it doesn't and it tends to do it more when the AC is running

 

No I dont, the truck has 35k could that be a possible problem?

 

Never heard of this?

 

No but seriously, what muffler brand are you running?

It may have loose baffling inside or it may be a bad mount where it meets the frame, did you have the shop that did the work initially look at their work?